1. Field of the Invention
The present invention relates to a fastening body for fastening various kinds of sheet members to a mounting portion, and more particularly to a strip-shape fastening body having a multiplicity of synthetic resin male engaging elements for a surface fastener which is used for suspending various kinds of screens such as a curtain, a screen for a projection, a blackout curtain, a suspended screen for an advertisement and the like to a suspending portion, or adhering an interior material such as various kinds of wallpapers, carpets and the like to various kinds of panels.
2. Description of the Related Art
Conventionally, there has been suggested, for example, in Japanese Utility Model Laid-Open Publication No. 6-64591 that a curtain is fastened to a curtain rail by fitting and fixing a strip-shape curtain fastening body in which synthetic resin male engaging elements constituted by a multiplicity of hooks and the like project from a surface of a substrate in a longitudinal direction of the curtain rail so as to be integrally formed with the flat substrate. Female engaging elements of a surface fastener provided along an upper end edge portion of the curtain are engaged with the curtain fastening body having the male engaging elements, at a time of mounting the curtain to the curtain rail having a generally C-shaped cross section, for example. Such a fastening body can be used for adhering an interior member such as various kinds of wallpapers, carpets and the like to various kinds of panels (a wall or a floor) as well as being used for the curtain, as disclosed in, for example, Japanese Utility Model Laid-Open Publication No. 5-70313.
The fastening body disclosed in these publications intends to firmly fix the fastening body to the curtain rail by forming rows of projections comprising intermittently protruding projections on one surface disposed along both side edges (selvedges) of a widthwise direction of the strip-shape fastening body, mounting the projection rows to fitting groove portions formed at both end edges of the curtain rail as a mounting body in the widthwise direction with their openings facing each other, for example, and pressing an inner wall surface of the fitting groove portions in the curtain rail by the projection rows, in addition to the structure mentioned above.
Accordingly, in accordance with the fastening body disclosed in each of the publications mentioned above, since the fastening body is elastically gripped by the inner wall of the fitting groove portions in the flat mounting body due to the projection rows, a firm fixation can be realized, however, since a rear surface of the flat substrate in the fastening body is brought into closely contact with a bottom surface of the mounting body in both cases, an engaging element protruding surface of the flat substrate of the fastening body becomes lower than the fitting groove portions by a height of the projection rows, and the engaging elements protruding from the flat substrate has less portion protruding from an upper surface of the mounting body, so that in order to secure a desired engaging rate, it is necessary to set a height of a rising portion of the engaging element higher by a height of the projection rows. This means that the rising portion of the engaging element becomes significantly bendable at the same thickness, so that it becomes hard to obtain an ideal engaging strength as the engaging element.
Further, in accordance with another fastening body disclosed in Japanese Utility Model Laid-Open Publication No. 5-70313, the projection rows mentioned above are provided on front and rear surfaces of the flat substrate, and the projection rows on the front and rear surfaces are fitted to the fitting groove portions. However, in the fastening body structured in the above manner, since a gap corresponding to the height of the projection rows is generated between the rear surface of the flat substrate and the bottom surface of the mounting body, the flat substrate of the fastening body is recessed inwardly to the mounting body by that gap when a product to which a female surface fastener is mounted is pressed against the fastening body to fasten it, so that an engagement with the male engaging elements is insufficiently achieved and it is most likely that a function as a fastening body can not be sufficiently obtained.
Further, in general, this kind of mounting body is continuously produced by extrusion as a long-shaped member having a predetermined cross section from a metal material. In this case, a cross sectional size of the shaped member is not necessarily uniform. Still further, a cross sectional shape of the mounting body is various, for example, and a transverse cross section between right and left fitting groove portions may be curved like a bow. On the other hand, the fastening body is made of a thermoplastic synthetic resin material and is continuously molded by an injection molding. However, taking a production efficiency and the like into consideration, it is not always a good measure to change a mold die and the like, and it is desired to mass produce the fastening bodies having the same width and the same shape.
Accordingly, as the fastening body disclosed in the publication mentioned above, in order to easily mount the fastening body to the companion mounting body by forming the projection rows along the end edges of the widthwise direction, it is necessary to set the height of the projection rows slightly lower than the height of the openings of the fitting groove portions. In the case that an accuracy therefor can not be obtained, a firm mounting can not be achieved, or it is impossible to mount the projection rows to the fitting groove portions.
Further, in the mounting body in which the transverse cross section is curved like a bow, when mounting the fastening body to the mounting body, a gap is generated between the curved surface of the mounting body and the fastening body, so that the flat substrate of the fastening body is recessed inwardly to the mounting body along the curved surface in the same manner as mentioned above when pressing the product in which the female surface fastener is mounted so as to fasten to the fastening body. Accordingly, a portion at which an engagement with the male engaging elements is insufficiently performed is generated in the center portion of the female surface fastener, so that there is a case that it is impossible to sufficiently achieve a function as the fastening body.